Total air temperature is a term used generally in aviation. In other applications it is called stagnation temperature. Total air temperature is measured by a specially designed temperature probe mounted on the surface of the aircraft or the interior walls of a turbine engine. The probe is designed to bring the air to rest relative to the aircraft. As the air is brought to rest, the air experiences an adiabatic increase in temperature. Therefore, total air temperature is higher than the static air temperature. Total air temperature is an essential input for calculating static air temperature and hence true airspeed. Because the total air temperature probes are often mounted in front of the jet engine it is often exposed to adverse conditions including high Mach numbers and icing conditions as well as water and debris, which may affect the reading provided by the temperature probe.